井中磁测在普查和勘探磁铁矿过程中,对快速评价磁异常,寻找井底、井旁磁性盲矿体,确定矿体形态、产状,以及在查漏定厚等方面,均取得了显著的地质效果.但目前广泛使用的国产JSZ型井中三分量磁力仪,是采用二次谐波原理设计制造的.由于其输出的二次谐波电压与外磁场不呈简单的 Wells magnetic survey In the process of surveying and exploration of magnetite, we have made great achievements in the rapid assessment of magnetic anomalies, finding the bottom of the well, the magnetic blind ore body near the well, the determination of ore body morphology, occurrence, etc. Significant geological effects.But now widely used domestic JSZ-type three-well magnetometer is designed and manufactured by the second harmonic principle.As the output of the second harmonic voltage and external magnetic field is not simple